Apparatus and method for multi-die interconnection

ABSTRACT

A semiconductor and a method of fabricating the semiconductor having multiple, interconnected die including: providing a semiconductor substrate having a plurality of disparate die formed within the semiconductor substrate, and a plurality of scribe lines formed between pairs of adjacent die of the plurality of disparate die; and fabricating, by a lithography system, a plurality of inter-die connections that extend between adjacent pair of die of the plurality of die.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/743,485, filed 15 Jan. 2020, which is a continuation of U.S.application Ser. No. 16/251,522, filed 18 Jan. 2019, which is acontinuation of U.S. application Ser. No. 16/019,882, filed 27 Jun.2018, which claims the benefit of U.S. Provisional Application No.62/536,063, filed 24 Jul. 2017, both of which are incorporated herein intheir entireties by this reference.

TECHNICAL FIELD

The inventions described herein generally relate to the computer chiparchitecture and fabrication field, and more specifically to a new anduseful computer chip architecture and computer chip manufacturingmethods in the computer chip architecture field.

BACKGROUND

While the concept of artificial intelligence has been explored for sometime, the modern applications of artificial intelligence have explodedsuch that artificial intelligence is being integrated into many devicesand decision-making models to improve their learning, reasoning, dataprocessing capabilities, and the like of the devices. The most apparentand broad applications of artificial intelligence include machinelearning, natural language processing, computer vision, robotics,knowledge reasoning, planning, and general artificial intelligence.

To be effective, many of the above-noted broad applications ofartificial intelligence require the consumption of extremely large datasets in the initial training of the artificial intelligence algorithms(e.g., deep learning algos, recurrent neural networks algos, etc.) beingimplemented in the specific applications and/or devices (e.g.,autonomous vehicles, medical diagnostics, etc.). Because the data setsused in training are often very large and the underlying computerarchitecture may not be specifically designed for artificialintelligence training, the training of an artificial intelligencealgorithm may require thousands of hours of data processing by theunderlying computer architecture. While it may be possible to scale orincrease the number of computers or servers used in ingesting andprocessing data sets for training an artificial intelligence algorithm,this course of action often proves to not be economically feasible.

Similar data processing issues arise in the implementation or executionof the artificial intelligence algorithms due to the large amount ofdata being captured, such as data originating from billions of Internettransactions, remote sensors for computer vision, and the like. Themodern remote distributed networked servers (e.g., the cloud) andonboard computer processors (e.g., GPUs, CPUs, etc.) appear to beinadequate for ingesting and processing such great volumes of dataefficiently to maintain pace with the various implementations of theartificial intelligence algorithms.

Accordingly, there is a need in the semiconductor space and specificallyin the computer chip architecture field for an advanced computingprocessor, computing server, or the like that is capable of rapidly andefficiently ingesting and processing large volumes of data for at leastthe purposes of allowing enhanced artificial intelligence algorithms andmachine learning models to be implemented. Additionally, these advancedcomputing systems may function to enable improved data processingtechniques and related or similar complex and processor-intensivecomputing to be achieved.

The inventors of the inventions described in the present applicationhave designed an integrated circuit architecture that allows forenhanced data processing capabilities and have further discoveredrelated methods and architectures for fabricating the integratedcircuit(s), packaging the integrated circuit(s), powering/cooling theintegrated circuit(s), and the like.

The below-described embodiments of the present application provide suchadvanced and improved computer chip architecture and related ICfabrication techniques.

SUMMARY OF THE INVENTION

In one embodiment, a semiconductor having multiple, interconnected die,the semiconductor comprises: a substrate comprising a semiconductorwafer; a plurality of die formed with the substrate; a circuit layerformed at each of the plurality of die; and a plurality of inter-dieconnections that communicatively connect disparate die formed with thesubstrate, wherein each of the plurality of inter-die connectionsextends between each pair of adjacent die of the plurality of die.

In one embodiment, the semiconductor wafer comprises a singular,integrally continuous form, and the plurality of die are formedintegrally and continuously with the singular, integrally continuousform of the semiconductor wafer.

In one embodiment, the semiconductor includes a plurality of scribelines, wherein each scribe line of the plurality of scribe lines ispositioned at the substrate between each pair of adjacent die of theplurality of die, wherein each of the plurality of inter-die connectionsextends over one scribe line of the plurality of scribe lines positionedbetween each pair of adjacent die of the plurality of die.

In one embodiment, each of the plurality of die comprises a protectivebarrier comprising a seal ring that surrounds active circuit regions ofeach of the plurality of die.

In one embodiment, the seal ring extends between the circuit layer ofeach of the plurality of die and intersecting edges of side faces and atop surface of each of the plurality of die.

In one embodiment, each end of each of the plurality of inter-dieconnections extends to a position on a top surface of each pair ofadjacent die of the plurality of die, and each of the plurality ofinter-die connections operably connects the circuit layers of each pairof adjacent die.

In one embodiment, the semiconductor includes a plurality of peripheralconnections distinct from the plurality of inter-die connections areformed along at least one side of a subset of the plurality of diepositioned along an outer periphery of the semiconductor.

In one embodiment, each of the plurality of inter-die connectionscomprises a conductive material that enables a transmission of signalsthereon between circuit layers of adjacent die of the plurality of die.

In one embodiment, each of the plurality of inter-die connectionscomprises a conductive material that is the same as the conductivematerial forming intra-die connections on the circuit layer of each die.

In one embodiment, the plurality of die are integrally formed with andmaintained integrally with the substrate without dicing each of theplurality of die from each other.

In one embodiment, the plurality of die include: (i) a first subset ofinterior die defining an interior of the semiconductor substrate,wherein the first subset of interior die have inter-die connections withadjacent die along all sides of the first subset of die; (ii) a secondsubset of peripheral die defining a periphery of the semiconductorsubstrate, wherein at least one side of each of the second subset ofexterior die are formed without inter-die connections.

In one embodiment, a method of fabricating a semiconductor havingmultiple, interconnected die includes providing a semiconductorsubstrate having: a plurality of disparate die formed within thesemiconductor substrate, and a plurality of scribe lines formed betweenpairs of adjacent die of the plurality of disparate die; andfabricating, by a lithography system, a plurality of inter-dieconnections that extend between adjacent pair of die of the plurality ofdie.

In one embodiment, the method of fabricating the semiconductor includesproviding a protective barrier at each of the plurality of die thatencompasses non-fabrication surfaces of each of the plurality ofdisparate die.

In one embodiment, the method of fabricating the semiconductor includesidentifying a largest usable geometry of the semiconductor substratethat includes an array or subset of the plurality of die; andfabricating a circuitry layer only at each of the plurality of diewithin the identified largest usable geometry.

In one embodiment, the method of fabricating the semiconductor includesfabricating one or more circuitry layers on each of the plurality ofdie.

In one embodiment, each of the plurality of inter-die connections extendfrom a first circuitry region of a first die of each adjacent pair ofdie to a second circuitry region of a second die of each adjacent ofpair of die.

In one embodiment, fabricating the plurality of inter-die connectionsincludes: setting a position of a die reticle offset a center of eachdie of each adjacent pair of die; setting the die reticle overlapping afirst circuitry region of a first circuitry region of a first die ofeach adjacent pair of die and a second circuitry region of a second dieof each adjacent of pair of die, wherein the die reticle comprisesgeometries for forming the plurality of inter-die connections; and uponsetting the die reticle into position, exposing by the lithographysystem the die reticle thereby forming the plurality of inter-dieconnections between adjacent pair of die.

In one embodiment, fabricating the plurality of inter-die connectionsincludes: setting a position of a first die reticle centered with afirst die of each adjacent pair of die; setting a position of a seconddie reticle centered with a second die of each adjacent pair, whereinthe position of the second die reticle overlaps a portion of the firstdie reticle, and wherein the first die reticle and the second diereticle comprise geometries for forming the plurality of inter-dieconnections between each adjacent pair of die; upon setting the firstdie reticle into position, exposing by the lithography system the firstdie reticle thereby forming a first portion of each of the plurality ofinter-die connections between adjacent pair of die; and upon setting thesecond die reticle into position, exposing by the lithography system thesecond die reticle thereby forming a second portion of each of theplurality of inter-die connections between adjacent pair of die.

In one embodiment, exposing the second die reticle builds the secondportion comprising a second layer of conductive material that overlapsthe first portion comprising a first layer of conductive material, andeach of the plurality of inter-die connections is defined by the overlapof the first layer and the second layer.

In one embodiment, a width of an overlapping portion of the first andsecond layers are diminished relative to a width of the non-overlappingportion of non-overlapping portions of each of the first and secondlayers.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic of a system 100 in accordance with one or moreembodiments of the present application;

FIG. 2 is a method 200 in accordance with one or more embodiments of thepresent application;

FIG. 3A-3D illustrate several schematics of a semiconductor substratewithout and with interconnections in accordance with one or moreembodiments of the present application; and

FIG. 4A-4G illustrate several schematics of a semiconductor substrateduring exposure processes and size reduction in accordance with one ormore embodiments of the present application.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description of preferred embodiments of the presentapplication are not intended to limit the inventions to these preferredembodiments, but rather to enable any person skilled in the art of tomake and use these inventions.

OVERVIEW

Traditional integrated circuit manufacturers may prepare a singlesilicon wafer with many die formed on the silicon wafer. Once each dieis formed on the silicon wafer, the integrated circuit manufacturer maythen separate each die on the silicon wafer by physically cutting thewafer and having each die separately packaged into a chip. In somecases, the manufacturer may install several of those disparate orseparate chips onto a same printed circuit board (PCB) to form anassembly and provide connections between the disparate chips so thatthey may communicate across the PCB assembly. The communicationconnections between the chips may typically be found in the PCB.However, when a multi-chip PCB is manufactured in this manner, thecommunication between disparate chips thereon becomes limited by theamount connectivity or bandwidth available in a given connection betweenthe disparate chips because the chips are in indirect communication viathe PCB. The bandwidth across chips (e.g., off-chip communication)formed on separate pieces of silicon may be multiple orders of magnitudelower compared to chips that remain and communicate on a same piece ofsilicon or die.

The embodiments of the present application provide technical solutionsthat resolve connectivity, communication, and bandwidth issues oftraditional integrated circuits and mainly, arising from integratedcircuits manufactured on separate pieces of silicon (e.g., off-dieintegrated circuits). The technical solutions of the embodiments of thepresent application enable multiple die to be maintained on a same orsingle substrate (e.g., a wafer) without partitioning away each die in awafer cutting process and further, while also establishing directcommunication connectivity between adjacent die on the single substrate.Accordingly, the embodiments of the present application function toprovide die-to-die connectivity on a single substrate or wafer.

The resulting substrate, however, has multiple die and consequentlybecomes a very large computer chip. Therefore, a number of technicalproblems relating to operational yield of the die on the large chip,packaging of the large chip, and powering/cooling of the large chip mustalso be solved.

1. An Integrated Circuit Wafer with Inter-Die Connections

As shown in FIG. 1, the semiconductor 100 illustrates an exampleintegrated circuit that includes a substrate 110, a plurality of die 120formed with the substrate 110, a circuit layer 125, a plurality ofinter-die connections 130, scribe lines 140, and input/output connects150.

The semiconductor 100 may be manufactured using any suitable lithographysystem and/or method that is configured to implement the one or moresteps of the methods described herein, including method 200.

The semiconductor 100 functions to enable inter-die communicationsbetween the plurality of die 120 formed with the single substrate 10.The inter-die connections 130 formed between adjacent die on thesubstrate no improves communication bandwidth and enables a reduction incommunication latency between connected die on the substrate no becausecommunication between each of the plurality of die 120 is maintained ona same large die (e.g., on-die communication). That is, the inter-dieconnections 130 formed between the plurality of die 120 effectivelyeliminate a need to for a first die of the plurality of die 120 to gooff-die (which increases latency due to transmission of signals using anintermediate off-die circuit) to establish communication with a seconddie of the plurality of die 120 since the first and the second die maybe directly connected with one or more inter-die connections or, at aminimum, indirectly connected via intermediate inter-die connectionsestablished between one or more die between the first and the seconddie. Such configuration(s), therefore, enabling increasedly fastercommunications and data processing between die when compared, at least,to communications between die not maintained on a same substrate (e.g.,a same wafer). Each of the plurality of die 120 remain on the singlesubstrate 110 and are not cut from the substrate 110 into individual diefor separate packaging into an individual computer chip. Rather, atformation, only excess die (e.g., die that are not provided withcircuitry or inactive die) along a periphery of the substrate 110 arepreferably removed from the substrate 110 and the remaining portions ofthe substrate 110 having the plurality of die 120 (e.g., active die) mayform a predetermined shape (e.g., a rectangular shape) with thesubstrate 110. The resultant substrate 110 after being reduced to shedexcess die and potentially following one or more additional refinementor IC production processes may then be packaged onto a board (e.g., aprinted circuit board (PCB) or an organic substrate).

The substrate 110 is preferably a wafer or a panel into and/or ontowhich die having a circuitry layer 125 on which active microelectronicdevices may be built. The circuitry layer typically defines one or moresurfaces on a die onto which circuits and various microelectronicdevices may be fabricated using a lithography system. The substrate 110is preferably formed of a silicon material (e.g., pure silicon), but maybe additionally or alternatively formed of any suitable materialincluding silicon dioxide, aluminum oxide, sapphire, germanium, galliumarsenide, an alloy of silicon and germanium, indium phosphide, and thelike. The substrate 110 may be a virgin wafer. Alternatively, thesubstrate 110 may include one or more layers formed therein where theone or more layers may include, but not limited to, a photoresist, adielectric material, and a conductive material. The photoresist beinglight-sensitive material may include any material that may be patternedby a lithography system. The photoresist may be positive photoresist ornegative photoresist.

Accordingly, the substrate 110 may be formed of any thin slice ofsemiconductor material that may be used for fabrication of integratedcircuits having varying diameters and shapes, but preferably thesubstrate 110 is formed in a circular shape and with a diameter of 300mm.

The lithography system may refer to any lithography system that printsimages of a reticle onto a substrate (e.g., a wafer) using light. Thelithography system may be a scanning projection system or a step andscan system, which may be alternatively referred to as a scanner or astepper. The lithography system may include any suitable exposure systemincluding one or more of optical lithography, e-beam lithography, X-raylithography, and the like.

The microelectronic devices, such as transistors, diodes, variouscircuits, and the like may be formed into and/or over the substrate 10using lithographic processes (e.g., optical lithography, etc.).

Each of the plurality of die 120 may be a block of semiconductingmaterial on which circuits may be fabricated. Each of the plurality ofdie 120 may be formed by an exposure process of silicon material of oron the substrate 10 and typically in a rectangular shape or squareshape. However, it shall be noted that the die 120 may take on anysuitable form including any geometric and non-geometric forms. Otherthan excess die that is removed from the substrate 10 during a substratereduction process, the plurality of die 120 are not cut or diced fromthe substrate 10 into individual die.

Additionally, each of the plurality of die 120 includes an alignmentpoint preferably at a center of each die. The alignment point may beused by the stepper of the lithographic system to align the photomaskand/or photoreticle with respect to each of the plurality of die 120before an exposure process. Further, each of the plurality of die 120may include a seal ring surrounding or covering a periphery (perimeter)of each of the die other than the circuitry layer (e.g., circuitfabrication surface) of each die. Accordingly, the seal ring may beprovided at the side surfaces of each die which extend in a normaldirection (i.e., perpendicular) with respect to the surface of thesubstrate no and further, located adjacent scribe lines 140.Additionally, or alternatively, a section of the seal ring surroundingeach die may be formed at a top surface of each die immediately beyondthe edges where each side face and the top surface of each dieintersects. In such embodiments, the seal ring may additionally beformed immediately beyond the intersecting edges of each die at the topsurface but before reaching a circuit layer 125 of each die. That is,the seal ring may additional cover an area of a die between an outerperiphery of the circuit layer 125 of a die and the edges where the topsurface intersects with each respect side face of the die. The circuitlayer 125 of each may include active circuits formed and/or positionedon a top surface (or bottom surface depending on perspective) of eachdie. The seal ring preferably functions to stop or mitigate propagationof damage and/or cracks in the structure of the semiconductor 100 into arespective die 120. Cracks and/or damage in the structure wouldotherwise allow contaminates to enter an active area (e.g., activecircuitry layer or the like) of a die and potentially alter the die'sfunctionality and/or performance, including tearing apart electricaland/or semiconductive connections.

As shown in FIG. 3C, the plurality of inter-die connections 130 functionto connect, at least, any two circuits (e.g., the inter-die connectionsmay connect a transmitting circuit and receiving circuit of two die,respectively) between two die of the plurality of die 120 on thesubstrate 110. That is, each inter-die connection 130 may be formed orprovided to extend from a first die to a second die located on thesubstrate 110. Preferably, an inter-die connection 130 may be formedbetween two adjacent die. Each inter-die connection may be formed of amaterial having a length and an endpoint at each respective end of thelength of material (e.g., two endpoints), where each respective endpointof an inter-die connection may terminate at a circuitry layer of adifferent die on the substrate 110. Accordingly, each respectiveendpoint of an inter-die connection may function to extend to a positionon a surface of a pair of die (preferably adjacent but can be any twodie) beyond a position of the seal ring on each of the pair of die.

In the case that the die are formed in a rectangular or similargeometric or substantially geometric shape, the inter-die connections130 may extend between two parallel or substantially parallel surfacesof the two-adjacent die. Accordingly, it is possible for a single die ofthe plurality of die 120 to be connected to more than one die dependingon the positioning of the die in the array of die on the substrate 110.When positioned in an interior of the substrate 110, the single die ofthe plurality of die 120 may be adjacent to four other die having atleast one surface that is parallel to one of the four side surfaces ofthe single die where one or more inter-die connections 130 may beformed. It shall be understood that while in preferred embodiments it isdescribed that the die may be formed as a rectangle (or other polygon),the die may be formed in any shape or manner suitable for preparing anintegrated circuit including non-traditional, non-geometric ornon-polygonal shapes.

The plurality of inter-connections 130 (global wires) are preferablywires or traces that function to conduct signals across two die. Theplurality of inter-connections 130 are preferably formed of a sameconductive material used to form intra-die connections (or local wires)between circuit elements of a single die. Additionally, oralternatively, the plurality of inter-die connections 130 may be formedof any suitable conductive material that may be the same or differentfrom materials forming other wires on a die or that may be the same ordifferent from materials forming the circuits on the die.

In a first implementation, the plurality of inter-die connections 130may be formed by offsetting the stepper of a lithographic system apredetermined distance from a center or alignment point of a single diesufficiently to allow an exposure to be performed for and between twoadjacent die rather than an exposure focusing on the circuitry layer 125of an individual die. Consequently, the exposure(s) that provides theinter-die connections 130 may be formed over the scribe lines 140.Additionally, the endpoints of an inter-die connection 130 may bepositioned or formed at interior position relative to a location of theseal ring of a die. Accordingly, while the inter-die connections 130 maybe formed at any suitable location between two die, the inter-dieconnections may be typically formed such that the respective endpointsof an inter-die connection 130 are positioned inwardly of the seal ringof the die on which it terminates such that each respective endpoint ofan inter-die connection 130 is positioned at some location between theseal ring and a center of the respective die. In a preferred embodiment,each respective endpoint of an inter-die connection may be positioned onthe circuit layer 125 of each respective die of a pair of interconnecteddie. However, it shall be noted that the respective endpoints may bepositioned ahead of the circuit layer 125 of each but still inwardlytowards a center of the die beyond a position of the seal ring.

In a second implementation, the plurality of inter-die connections 130may be formed using a multi-exposure process in which exposures forcreating the circuitry layer and the inter-die connections 130 aremaintained in alignment while exposing a layer of photoresist multipletimes. While in alignment, the exposure configured for creating theinter-die connections 130 preferably has a (slightly) larger geometryand/or size than the die. In this way, this area of a die having theinter-die connections 130 may be exposed multiple times (e.g., a doubleexposure).

Accordingly, in some embodiments, the first implementation and thesecond implementation for creating the inter-die connections 130 may becombined to achieve the inter-die connections throughout a samesubstrate 110.

The scribe lines 140 (or saw street) function to indicate a locationbetween two disparate die on the substrate 110 where the substrate 110would typically be cut for forming individual die. The scribe lines 140may typically be centered between a pair of die or adjacent die and inmany cases, have a width similar to a width of a saw used for cuttingwafers and the like. Accordingly, each scribe line 140 may extendlongitudinally and/or latitudinally along a surface of the semiconductor110 and typically extend parallel with or substantially parallel withside surfaces of the die. In a preferred embodiment, no circuitry orother device elements would be formed on or over the scribe lines 140,as these elements would most likely be severed or damaged during acutting process of the substrate 110. In a traditional die productionprocess, however, some testing structures or testing devices may existnear or at the scribe lines and these testing structures may be used fortesting the circuitry or process prior to dicing die on a wafer intoindividual pieces.

The input/out (I/O) connections 150 (or fanouts) preferably enable thearray of interconnected die 120 of the semiconductor 100 to interactwith off-die devices and/or devices external to the semiconductor 100.Preferably, the I/O connections 150 may be formed and/or arranged alongone or more sides of the plurality of die 120. In such preferredembodiments, the I/O connects 150 may be formed along a side of theplurality of die 120 where the plurality of die 120 are without anadjacent die. That is, the plurality of die 120 may include a subset ofdie forming an interior and another subset of die forming an outerperiphery of the plurality of die 120. While, in some embodiments, thesubset of die forming the outer periphery of the plurality of die 120have inter-die connections at one or multiple side surfaces withadjacent die, these outer peripheral die may also have side surfaceswhich do not have inter-die connections to adjacent die because thereare no other die beyond these outer peripheral die.

The I/O connections 150 may be formed using a same exposure techniqueand/or a same conductive material as used in fabricating the inter-dieconnections 120. It shall be noted that the I/O connections 150 may befabricated using any suitable method and/or signal transmittingmaterial.

2. Method of Producing an Integrated Circuit Wafer with Inter-DieConnections

As shown in FIG. 2, a method 200 for producing or fabricating a largesemiconductor having a plurality of die and a plurality of inter-dieconnections includes providing a semiconductor substrate S210,fabricating one or more circuitry layers on a plurality of die of thesubstrate S220, fabricating a plurality of inter-die connections S230,and reducing a size of the semiconductor substrate. The method 200 mayoptionally or alternatively include identifying a largest square of thesubstrate S215, providing self-correcting mechanisms to the die S222,and providing a protective barrier encompassing portions of theplurality of die S225.

Generally, the method 200 enables the fabrication of a large die for alarge integrated chip. The method 200 provides a wafer onto which aplurality of die are formed and are maintained on the same wafer. Thatis, the plurality of die onto which circuitry are provided via alithography process are not cut or diced either individually or ingroups away from any other of the plurality of die having circuitry onthe wafer. The method provides inter-die (e.g., between die) connectiontechniques that allow for fabrication or installation of signalconducting wires or traces between at least two die on the wafer. Themethod 200 may implement the inter-die connection techniques between allor substantially all pairs of die existing on the wafer such thatcommunication between any two die across the entire board may beachieved. A technical advantage of such method and resultingconfiguration is enhanced communication bandwidth and reduce latency incommunication between the plurality of interconnected die. That isbecause the inter-die connections established between each pair of dieon the wafer enable direct or sometimes indirect communication channelsthat stay on-die (as previously discussed in section i) rather thanoff-die. Accordingly, such configuration enables data to be processedmultiple orders faster (e.g., improved throughput) than in traditionalchip architecture. Additionally, one or more implementations of themethod 200 accomplishes the inter-die connections without usingstitching techniques that are known in the art.

S210, which includes providing a substrate, functions to provide asubstrate to a lithography system for building an integrated circuit.The substrate is preferably a wafer but may be any semiconductormaterial that may be used in manufacturing a semiconductor device, suchas a panel or the like. The wafer provided to the lithography system maybe any standard size wafer ranging from 25 mm to 450 mm or non-standardsize wafer. S210 may provide the wafer to a wafer stage or other wafermounting surface of the lithography system.

In one example, S210 may provide a circular or substantially circularwafer being approximately 300 mm in size. In such example, the waferpreferably includes a plurality of die each having a gross size of17.1×30.0 mm (e.g., exposure pitch), as shown in FIG. 3A. The exposablesurface of the wafer, however, may be slightly smaller than the grossexposure pitch of a die. The exposable surface of the wafer may includeany or all surface portions of the wafer; however, in a preferredembodiment, the exposable surface preferably includes the surfaces ofthe wafer that fits within an optimal (or selected) geometry (e.g., arectangle, a square, etc.). Additionally, or alternatively, between eachpair of die (along a planar surface of the die) may be included a scribeline indicating a location at which a saw may be used to safely cut thewafer without damaging a die. It shall be noted that while each waferprovisioned to the lithography system may include or identify scribelines, this method preferably avoids individually cutting the wafer toseparate the die with circuitry fabrication into individual die. Rather,the scribe lines of the wafer may be used to reduce excess (or unused)die from the wafer while maintaining the die with circuitry fabricationsof the wafer. That is, the scribe lines along a periphery of the wafermay be used to reduce the wafer to an optimal or selected geometry oncethe plurality of die have been exposed and may be ready for a subsequentprocess, such as packaging, etc.

S210 may additionally provide a protective barrier or seal ringencompassing the non-fabrication surface(s) or non-circuitry layer ofeach of the plurality of die of the wafer. The dimensions of the sealring may incidentally reduce, by a small amount, the available circuitryfabrication surface of each of the plurality of die. In someembodiments, the protective barrier may not be formed along exteriorside surfaces of subset of the plurality of die forming an outerperiphery thereof.

Prior to performing an exposure of the wafer, S215 optionally includesidentifying a largest usable geometry of the wafer. A preferablygeometry of each of the plurality of die of the wafer is preferably arectangle (or square). In such case, S215 functions to identify alargest square array of die that will be used during circuitryfabrication on each die. For example, a typical 300 mm wafer may includea total of one hundred (100) total die. In such example, in identifyinga largest square array of die, S215 may identify only eighty-four (84)full die in a 12 die×7 die square configuration, as illustrated in FIG.3B. A technical advantage of such square configuration is that workloadsfor implementing artificial intelligence (AI) machine learningalgorithms and the like is made easier with a square configuration.

Accordingly, as shown in FIG. 3B, S215 functions to identify an optimalfabrication area (including full die) of the wafer to be used incircuitry fabrication and consequently, areas of the wafer outside ofthe optimal fabrication region that will be cut from the wafer in areduction process.

S220, which includes forming a circuitry layer, functions to produce oneor more circuitry layers on each of the plurality of die in afabrication region (as defined in S215) of the wafer by exposing asurface of each of the plurality of die using a lithography system. Thecircuitry layer of each of the plurality of die may be formed to includeany number and type of circuitry and/or microelectronic devices, such asa plurality of logic devices and transistors. The logic devices of thecircuitry layer of each die may include normal operating logic for agiven die as well as redundancy logic devices that allow a given die onthe wafer to repair itself.

S222, which optionally includes providing self-correcting mechanisms tothe die, functions to provide logic devices to the circuitry layer ofthe die that function to mitigate yield problems associated a largewafer having a plurality of interconnected die. In a traditional chipmanufacturing process, each die formed on a wafer may be diced andindividually packaged into a single chip. Thus, if the single chipmalfunctions in some manner, the malfunctions are isolated to the singlechip. This may be ideal in the circumstance of a multi-chip board. Bycontrast, in a preferred embodiment of this application, multiple dieare maintained (i.e., not diced) on a single large wafer. In suchembodiment, when one or more die on the single large multi-die wafermalfunctions, the malfunctioning of the one or more die may affect orpropagate through to neighboring and/or indirectly interconnected die.In such circumstance, the malfunctioning of one or more die on thesingle large multi-die wafer may be compounded throughout the singlelarge multi-die wafer due to the interconnection of the multiple die andreliance on connected die for signal throughput.

Accordingly, the malfunctioning of a single die or more of a singlelarge multi-die wafer may compoundly reduce the yield of the largewafer. To address this technical problem, S222 functions to fabricateand/or provide within each die self-correcting mechanisms that functionto correct problems that arise with each die. Preferably theself-correcting mechanisms include logic devices, such as redundancylogic devices that function to enable a die to self-repair a malfunctionor, at least, continue functioning through different mechanisms providedby the redundancy logic devices.

S220 includes providing to a stepper or scanner of the lithographysystem photoreticles or photomasks for each layer of circuitry that isdesired for each of the plurality of plurality of die. The photomasksmay be used to specifically expose with a light source certaingeometries in a photoresist layer provided to a fabrication surface ofeach die. As in traditional lithography processes, the exposed portionsof the photoresist layer may be etched or washed away while theremaining unexposed areas are maintained. The remaining silicon layerthat was not etched away may be used to define a circuitry layer. In apreferred embodiment, the photomask used for exposing geometries ontothe photoresist layer of the wafer has a shape and dimensions similar toor matching that of a single die. In such case, a single shot exposureusing a given photoreticle may typically be sufficient to define acircuitry layer on a fabrication surface of a given die on the wafer.However, as discussed below with respect to the exposure and fabricationof the inter-die connections or wires, it may be possible to use anenlarged photoreticle that is capable of exposing a circuitry layerwithin a fabrication surface or region of a die and additionally and/orseparately, expose a region between a pair of die to provide inter-dieconnectivity (e.g., add signal wires).

Optionally, S225, which includes providing a protective barrier or sealring, functions to expose an area surrounding a given die on the waferto protect the die from potential contaminates that may permeate intothe die. The seal ring may additionally be used to define a fabricationregion for a given die, in that, the areas of the die that are notencompassed by the seal ring may typically be used for deposition ofmaterial for fabricating circuitry. In many instances, the fabricationregion for a die may a surface of the die that is perpendicular to anexposure device of the lithography system. However, it shall be notedthat any surface of a given die may be used as a suitable fabricationsurface.

The provisioning of the protective barrier (S225) may be performedpreferably contemporaneously (e.g., at a same time) with the fabricationof the circuitry layers of the die. Additionally, or alternatively, theprotective barrier may be provided to the die to avoid or reduce anypotential contamination from various chip manufacturing processes, suchas a wafer reduction process or the like. In several embodiments, theseal ring defines an area within a die (e.g., the circuitry layer) ontowhich circuits and other devices may be formed onto the die.Additionally, this area defined by the seal ring may also accommodateone or more endpoints of the inter-die connections (e.g., the endpointsof the inter-die connections may be formed on the circuitry layerdefined by an inside area of the seal ring.

S230, which includes fabricating a plurality of inter-die connections,functions to provide connectivity and/or communication means betweencircuitry layers of a first circuitry region of a first die of a diepair and a second circuitry region of a second die of the same die pair.An inter-die connection may refer to or relate to a physical connectionestablished between two die on a same wafer. In a preferred embodiment,the inter-die connection may include a single wire or trace that extendsfrom a circuit of a first die to a circuit of a second die. Theinter-die connection is preferably established using a same lithographysystem used in fabricating the circuitry layers and intra-die (e.g.,within die wires) connections of each of the plurality of die on thewafer. That is, the inter-die connection may be manufactured between dieby implementing the lithography system to expose an area between the diethat also includes surfaces portions of each of the die defining thearea between.

S230 may be implemented before or after the intra-die connections arefabricated using the lithography system. Alternatively, the exposure andfabrication of the intra-chip wires and the inter-die connections may beperformed contemporaneously or at a same time. Preferably, S230implements an exposure and fabrication of the inter-die connections oncethe circuitry layer(s) of the die as well as the intra-chip wires of thedie are complete. In this way, the lithography system may necessarilyadjust its position relative to a die only after the circuitry and wiresof the die are in place. In this way, realignment of the lithographysystem to a center or alignment point(s) of a die is not required.

S230 includes providing a photoreticle to a stepper or scanner of thelithography system that includes geometries for exposing photoresistlayers or the like for fabricating the inter-die connections. Thegeometries for each inter-die connection may be sufficiently long enoughto extend from one surface of a first die to a second surface of asecond die. Accordingly, an extent or length dimension of giveninter-die connections may be depend, in part, on a pitch or distancebetween circuitry surfaces of two die communicatively connected usingthe inter-die connections.

Additionally, or alternatively, S230 may include multiple exposuresimplemented using multiple photomasks to achieve connectivity betweendifferent circuits of a pair of die. In some instances, it may benecessary to provide inter-die connections that extend higher in heightand/or longer in length than some inter-die connections.

Preferably, S230 functions provide inter-die connections by exposingareas between each pair of die on the substrate such that the ends ofeach inter-die connection straddle single rings of the die. That is,each end of an inter-die connection may be fabricated such that it ispositioned inwardly of an encapsulation of the respective seal rings therespective die pair that is being connected.

Since S230 functions to provide the inter-die connections between thedie pair on the un-partitioned substrate, each of the inter-dieconnections is fabricated such that a portion of the extension of theinter-die connections extends over scribe lines that extend, inparallel, with side surfaces of and between a pair of die.

Additionally, S230 may function to configure the lithography system toenable the exposure for fabricating the inter-die connections outside ofthe circuitry layer or circuitry fabrication regions of the die.

In one implementation, without changing a size of a photomask, S230functions to configure the lithography system to move in an offsetposition along an X-Y axis relative to a planar surface of the wafer inorder to position the photomask that defines the geometries of theinter-die connections, as shown in FIG. 4A. Typically, the lithographysystem is configured to align with one or more alignment points of eachdie. Accordingly, during a lithography process a center point of aphotomask used to expose circuitry geometries is aligned with a centerpoint of the plurality of die while still allowing for an offsetexposure of each individual to form the inter-die connections betweenadjacent pair of die. In some embodiments, a center point of the lightsource providing light for the exposure may additionally be in alignmentwith the center points of the photomask as well as the die.Additionally, or alternatively, there may be several alignment pointsthat may be used to align a die, photomask, and light source.

Further, in this implementation, S230 may configure the lithographysystem to offset a specific pitch in multiple directions of a single diein order to expose between die that are adjacent the single die. Forinstance, in the circumstance that a given die is positioned in aninterior of a wafer, the given die may surround up to four or moreadditional die. Thus, the establish connectivity between the given dieand the surrounding die, the lithography system may be configured tomove in an offset manner from a center or alignment points of the givendie. Thus, the lithography system, in this example, may move a samepitch in the positive and negative Y-direction and a same pitch in thepositive and negative X-direction to establish inter-die connectionsbetween the given die and the surrounding die. Accordingly, S230 mayfunction to configure the lithography system differently according to anumber of inter-die connection regions that exist between a given dieand surrounding die.

In a second implementation, rather than offsetting a position of thephotomask or lithography system relative to a die, S230 may function toprovide a larger photomask that is sufficiently large such that anexposure may be performed in an inter-die connection region that existsbetween die. As mentioned previously, an inter-die connection region mayadditionally include some portions of the circuitry fabrication regionof a die. In this way, if the photomask is sufficiently large, it may bepossible to expose all inter-die connection regions surrounding a givendie such that deposition of inter-die connection material may bedeposited at the same time to establish connections of the given die tomultiple surrounding die.

Additionally, or alternatively, the photomask may be enlarged withrespect to at least one side (or more than one side but not all sides ofthe photomask) such that an exposure for inter-die connections may bemade for at least one side (e.g., a right side) of a given die beforethe photomask must be replaced with another photomask that is designedfor exposure for inter-die connections of another side (e.g., a leftside) of the given die. Additionally, or alternatively, the photomaskmay be enlarged with respect to all sides such that an exposure forinter-die connections may be made for all sides of a given die (e.g., amulti-exposure process).

In a third implementation, S230 may function to configure thelithography system and/or provide a photomask that produce exposureswith varying topologies. For instance, S230 may configure thelithography system and/or provide a photomask that enables a startopology exposure that allows the fabrication of inter-die connectionsbetween a plurality of die in a star topology configuration.

Additionally, or alternatively, S230 may configure the lithographysystem to provide exposures for fabricating the inter-die connectionseither over alignment and/or process features that may lie in the sealregion and/or region between a pair of die on the wafer. Accordingly, insome embodiments, the inter-die connections are fabricated at locationsthat avoid blocking access to the alignment and process features thatenable testing and alignment of the wafer and/or other processingdevices.

In a fourth implementation, S230 may function to configure thelithography system to adjust an angle positioning of a light source ofthe lithography system to project light through a photomask to exposegeometries for inter-die connections onto the semiconductor substrate.In such implementation, the photomask may be maintained in an originalalignment (e.g., circuitry fabrication alignment) with the die and thus,offsetting or repositioning the photomask may not be necessary.

In a fifth implementation, S230 may function to implement a stitchingtechnique to fabricate each of the plurality of inter-die connectionsbetween adjacent pair of die. In a preferred embodiment, S230 mayfunction to set a first photoreticle in a positioned centered over afirst die of an adjacent die pair and set a second photoreticle in apositioned centered over a second die of the adjacent die pair, as shownby way of example in FIGS. 4E-4F. In such preferred embodiment, thefirst photoreticle and the second photoreticle may have overlappingsections that overlap at least at a region (e.g., scribe line region,etc.) between the adjacent pair of die.

In such fifth implementation, once the first photoreticle is set intoposition, S230 may function to use the lithography system to expose thefirst photoreticle and once the second photoreticle is set intoposition, S230 may function to expose the second photoreticle.Preferably, the first and the second photoreticle include complementarygeometries for stitching together inter-die connections in anoverlapping manner. That is, the first photoreticle may include a firstgeometry for fabricating a first portion comprising a first layer ofconductive material for a given inter-die connection. The secondphotoreticle may include a second geometry for fabricating a secondportion comprising a second layer of conductive material for the giveninter-die connection. After the second exposure of the secondphotoreticle, the second portion may function to overlap the firstportion thereby creating a composited or stitched inter-die connectionbetween the adjacent pair of die.

Preferably, a width at a distal end of the first portion may bediminished with respect to a width of a proximal end of the firstportion nearest or positioned on the first die. Similarly, a width at adistal end of the second portion may be diminished with respect to awidth of a proximal end of the second portion nearest or positioned onthe second die of an adjacent pair. The respective sections of the firstportion and the second portion may be positioned so that they overlapand join together, as shown by way of example in FIG. 4G. Once joined,the conductive material at the overlapping section of the joint mayfunction to expand to achieve a width that is a same or substantiallythe same as a width at the proximal ends of each respective portions.

As shown in FIG. 4B, S230 may additionally function to configure thelithography system to expose the outer perimeter of the plurality of dieat the periphery of the semiconductor substrate for fabricatingconnections to a system (e.g., fan-outs, die-to-system interconnect, asshown in FIG. 3D). The resulting die-to-system interconnect may spanfrom die on the outer periphery of the semiconductor substrate toconnect with one or more system components that may be positioned off ofthe substrate, as shown in FIG. 3Bs.

S240, which includes reducing a size of the semiconductor substrate,functions to reduce the semiconductor to a size that includes theplurality of die with circuitry and inter-die connections as well as thedie-to-system interconnections. The general reduction size of thesemiconductor substrate may generally be determined in S215 and may beadjusted slightly to include the die-to-system interconnections, asshown in FIG. 4C. Resultantly, S240 cuts from the semiconductorsubstrate the excess or unused die and provides a reduced semiconductorsubstrate, as shown in FIG. 4D, for additional computer chipmanufacturing processes (e.g., chip packaging, etc.).

It shall be understood that the method 200 is an exemplary method thatmay be implemented in any suitable order to achieve the inventionsand/or embodiments of the inventions within the purview or that may beeasily contemplated in view of the disclosure provided herein. Thus, theorder and process steps should not be limited to the exemplary orderprovided herein.

The methods of the preferred embodiment and variations thereof can beembodied and/or implemented at least in part as a machine configured toreceive a computer-readable medium storing computer-readableinstructions. The instructions are preferably executed bycomputer-executable components preferably integrated with thelithography system and one or more portions of the processors and/or thecontrollers implemented thereby. The computer-readable medium can bestored on any suitable computer-readable media such as RAMs, ROMs, flashmemory, EEPROMs, optical devices (CD or DVD), hard drives, floppydrives, or any suitable device. The computer-executable component ispreferably a general or application specific processor, but any suitablededicated hardware or hardware/firmware combination device canalternatively or additionally execute the instructions.

Although omitted for conciseness, the preferred embodiments includeevery combination and permutation of the various methods, apparatus, andsystems described herein.

As a person skilled in the art will recognize from the previous detaileddescription and from the figures and claims, modifications and changescan be made to the preferred embodiments of the invention withoutdeparting from the scope of this invention defined in the followingclaims.

What is claimed is:
 1. A semiconductor wafer comprising: a body, thebody of the semiconductor wafer comprising a single, continuoussubstrate formed with semiconductor material; a plurality of distinctdie lithographically formed within the body of the semiconductor wafer,wherein each of the plurality of distinct die is integrally formed withthe semiconductor material of the body of the semiconductor wafer and isnot diced from the body; and a plurality of inter-die circuitconnections that each: (i) extend across the semiconductor wafer and(ii) connect distinct pairs of die of the plurality of distinct dieformed within the body of the semiconductor wafer.